On-Line Program for CT Quality Control

Purpose: An on-line quality control program (QC) for computed tomography (CT) scanners was developed in Porto Alegre and in Sao Paulo, two main cities of Brazil, led by two university medical physicists, and coordinated by the Health Technology Task Group of the International Union for Physical and Engineering Sciences in Medicine. Method and Materials: Using a combination of commercial phantoms and software and in-house computer programs, and following the methodologies developed by the AAPM and the ACR, the following parameters were documented with the purpose of being periodically monitored: CT protocols for adult and pediatric head and abdomen scans, evaluation of scanner performance and image quality, and CTDI information from DICOM headers for the head and abdomen studies. The initial evaluations were performed by medical physicists, who then trained the CT technologists at the institutions to scan the phantoms, extract the information from the DICOM headers and transmit the data to the two Brazilian universities, which collated and analyzed the results.Results: The problems encountered in the implementation of the on-line program in over 30 CT facilities, especially regarding DICOM interconnectivity issues, will be reviewed. Initial results showed that although most scanners complied with AAPM/ACR requirements regarding image quality, there was a wide range of doses for each procedure among and even within the institutions, pointing out to the lack of optimized image acquisition protocols. Conclusion: The need to implement QC programs for CT has been recognized for a long time. However, the scarcity of diagnostic medical physicists in resource-limited settings requires innovative solutions such as this on-line program that allows local data gathering and remote data analysis.